Bottom Line:
We identified 13 articles matching the inclusion criteria.All studies had been performed during the last decade.Due to lack of consensus on how microarray data are presented, possible general trends found across the studies are difficult to extract.

Purpose: This article provides a review of the transcriptomic expression profiling studies that have been performed on meningiomas so far. We discuss some future prospects and challenges ahead in the field of gene expression profiling.

Methods: We performed a systematic search in the PubMed and EMBASE databases in May 2010 using the following search terms alone or in combination: "meningioma", "microarray analysis", "oligonucleotide array sequence analysis", or "gene expression profiling". Only original research articles in English that had used RNA hybridized to high-resolution microarray chips to generate gene expression profiles were included.

Results: We identified 13 articles matching the inclusion criteria. All studies had been performed during the last decade.

Conclusions: The main results of the studies can be grouped in three categories: (1) several groups have identified meningioma-specific genes and genes associated with the three WHO grades, and the main histological subtypes of grade I meningiomas; (2) one publication has shown that the general transcription profile of samples of all WHO grades differs in vivo and in vitro; (3) one report provides evidence that microarray technology can be used in an automated fashion to classify tumors. Due to lack of consensus on how microarray data are presented, possible general trends found across the studies are difficult to extract. This could obstruct the discovery of important genes and pathways universally involved in meningioma biology.

Fig1: Principle behind microarray analysis (Human Genome Microarray, Applied Biosystems). mRNA extracted from a biological sample is labeled and converted into cDNA. On a microarray slide (“chip”), thousands of oligonucleotides representing individual genes are positioned in predefined positions. If the corresponding cDNA is present, it will hybridize to the oligonucleotide. By a chemiluminescent reaction, the presence of cDNA can be measured

Mentions:
Microarray chips of the size of histology slides including all known human genes are currently manufactured with high precision. The main methods for the production of such chips are based on robotic spotting of cDNA probes or oligonucleotides to a surface [3] (Fig. 1). By labeling the RNA in the samples at study and hybridization to the corresponding gene probes on the microarray chip it is subsequently possible to measure the abundance of every gene expressed at time of tissue sampling. The measured signals are then converted to numerical values and interpreted with bioinformatic tools to produce the gene expression profile.Fig. 1

Fig1: Principle behind microarray analysis (Human Genome Microarray, Applied Biosystems). mRNA extracted from a biological sample is labeled and converted into cDNA. On a microarray slide (“chip”), thousands of oligonucleotides representing individual genes are positioned in predefined positions. If the corresponding cDNA is present, it will hybridize to the oligonucleotide. By a chemiluminescent reaction, the presence of cDNA can be measured

Mentions:
Microarray chips of the size of histology slides including all known human genes are currently manufactured with high precision. The main methods for the production of such chips are based on robotic spotting of cDNA probes or oligonucleotides to a surface [3] (Fig. 1). By labeling the RNA in the samples at study and hybridization to the corresponding gene probes on the microarray chip it is subsequently possible to measure the abundance of every gene expressed at time of tissue sampling. The measured signals are then converted to numerical values and interpreted with bioinformatic tools to produce the gene expression profile.Fig. 1

Bottom Line:
We identified 13 articles matching the inclusion criteria.All studies had been performed during the last decade.Due to lack of consensus on how microarray data are presented, possible general trends found across the studies are difficult to extract.

Purpose: This article provides a review of the transcriptomic expression profiling studies that have been performed on meningiomas so far. We discuss some future prospects and challenges ahead in the field of gene expression profiling.

Methods: We performed a systematic search in the PubMed and EMBASE databases in May 2010 using the following search terms alone or in combination: "meningioma", "microarray analysis", "oligonucleotide array sequence analysis", or "gene expression profiling". Only original research articles in English that had used RNA hybridized to high-resolution microarray chips to generate gene expression profiles were included.

Results: We identified 13 articles matching the inclusion criteria. All studies had been performed during the last decade.

Conclusions: The main results of the studies can be grouped in three categories: (1) several groups have identified meningioma-specific genes and genes associated with the three WHO grades, and the main histological subtypes of grade I meningiomas; (2) one publication has shown that the general transcription profile of samples of all WHO grades differs in vivo and in vitro; (3) one report provides evidence that microarray technology can be used in an automated fashion to classify tumors. Due to lack of consensus on how microarray data are presented, possible general trends found across the studies are difficult to extract. This could obstruct the discovery of important genes and pathways universally involved in meningioma biology.